Synchronism indicating and control system



Feb. 6, R; N, T D 2,189,596

, SYNCHRONISM INDIGATING AND CONTROL SYSTEM Original Filed April 15', 1932 Y WITNESSES: I INVENTOR m Raga/7 A/Smddard Q 44' I 9 %M. %mL 7 ATTO EY Patented Feb. 6, 1940 UNlTEDSTATES PATENT OFFICE SYNCH RONISM INDIOATING AND CONTROL SYSTEM Ralph-N. Stoddard, Pittsburgh, Pa., assignor to Westinghouse Electric and Manufacturing Company, a corporation of Pennsylvania Original application April 15, 1932, Serial No. 605,546. Divided and this application May 22, 1937, Serial No. 144,175

. 7 Claims.

1 system which shall be of simple construction, re-

provide for indicating the'degree of synchronism between two alternating current power lines or systems at a point remote from the place where the indication is originated and for causing the systems to be connected from the remote point so? all over a single control and signalling circuit.

Another object of the invention is to provide for indicating at a remote point the degree of synchronism between two alternating current power lines or systems controlling the operation of the connecting breaker and indicating its position over a single signalling channel.

A further object of the invention is to provide for indicating the degree of synchronism, closing the connecting breaker and indicating the 30 position of the breaker over a single signalling channel by means of oscillation generators and receivers operating at different frequencies.

These and other objects of the invention will become more apparent from a study of the fol- 5'lowing detailed description in conjunction with the drawing in which the single figure is a diagrammatic view of a system embodying the principal features of the invention. Referring now to the drawing, the system ther 40' shown. is arranged to transmit an indication of the degree of synchronism between two portions of a power system to a remote point and to control and supervise the operation of a circuit breaker from the remote point for connecting the 48 'two portions of the power system together. The

two portions of the power system are represented by conductors 4| and 42 which are to be connected together by means of a circuit breaker, shown generally at 43. The circuit 50 breaker 43 is provided with the usual closing solenoid 44 and tripping solenoid 45, both of which are controlled by an actuating relay 45.

In order to indicate the degree of synchronism' ,between the two portions of the system so that 55 an operator may be informed of the proper time to close the circuit breaker 43, potential transformers 41 and 48 are connected as shown, to the conductors 4| and 42, respectively, and to the double primary winding of a grid transformer 49 the secondary winding of which is connected in 6 the grid circuit of a vacuum tube 5|). The plate circuit of the vacuum tube 50 is connected to an insulating transformer 52 which is connected to the single control and signalling circuit, represented by the conductors 22. It will be observed 10 that, with this circuit arrangement, the frequencies of both portions of the power systems will be applied to the control and signaling circuit '22.

While the transformer 49 is shown and described as having a double primary winding and a single secondary winding, it will be readily apparent that two separate transformers may be used having the primary windings connected as shown in the drawing and the secondary windings connected in series circuit relation.

An amplifier shown generally at 53 is connected to the control and signalling circuit and has connected in its output circuit a filter circuit, shown generally at 54.

The amplifier 53 is of well-known construction comprising a second insulating transformer'24 for connecting the signalling circuit '22 to the grid circuit of a three-electrode vacuum tube 25 and a plate, transformer 26, connected as shown in the plate circuit of the vacuum tube 25. The entire output of the amplifier 53 is then applied through the plate transformer 26 to the filter circuit 54.

The filter circuit 54 comprises an inductance coil 29 and a variable condenser 30 which are connected in series. circuit relation across the secondary of the plate transformer 26. As will be readily understood, the condenser 30 may be adjusted so that only a predetermined frequency is permitted to traverse the filter circuit 54 while all other frequencies are excluded therefrom.

In this instance, the variable condenser 30 in filter circuit 54 is adjusted to tune it tothe frequency ofthe power systems. This particular frequency is then applied to a synchronization indicator, shown generally at 55, which comprises a three-electrode vacuum tube 56 having its grid circuit connected to the filter circuit 54, as illustrated, and its plate circuit connected to an indicating meter 51.

The indicating meter 51 may be of any suitable ,type which will indicate either a maximum scale deflection or a zero scale deflection when the frequency of the two portions of the power system tween the two portions of the power system, an oscillation. generator; shown generally at 88, is

connected to the control and signalling conductors 22 through a transformer M, as shown. The oscillation generator 50 is'xof well-known construction and comprises an inductance coil l i connected in the plate circuit of a three-electrode vacuum tube !2 and a variable condenser Ed by means of which the frequency of oscillation of the generator may be varied in the usual manner.

Any suitable current source may be used for heating the filament of thevacuum tube i2 and for. applying thereto the desired plate and grid potentials. The generator to is arranged to supply oscillations of a predetermined frequency to the control and signalling circuit when a switch 5i in the grid circuit of the vacuum tube 32 of this generator is closed.

"The frequency generated by the oscillation generator fill is transmitted overthe signalling channel 22 to the apparatus station to operate a receiver 83 thereat. The receiver 63 is connected to the signalling channel 22 through an amplifier 62 and filtercircuit 28 similarto the amplifier 53 and filter circuit 56, respectively, at the other station.

Relay 34 is energized and operated in response to the operation of the receiver63 to close an 7 obvious energizing circuit for the actuating relay 46L. 'Upon closure of relay 45, the closing coil it of the breaker 43 is energized to close the breaker. In order to give an indication back to the operatorj that the circuit breaker 43 has closed, a

supervisory relay M is providedand is disposed,

to initiate the operation of a second oscillation generator, shown generally at 55, which is connected to the control and signalling circuit; as shown, and arranged to generate a frequency iiferent from any of the other frequencies appliedto this circuit. The supervisory relay 64 is energized when contact members 43a are bridged on closure of the circuit breaker 43 and is 'deenergized when these contacts areopened on the tripping of the circuit breaker.

The oscillations produced by the generator 65 areamplified by the amplifier 53 and applied to a second filter circuit 65 which is tuned to receive only oscillations of the frequency supplied from this generator. The oscillations which are per- .mitted topass through-the filter circuit 65 are received by a second receiver" including the threeelectrode vacuum tube 33, shown generally at t'l, thereby causing receiving relay 33 to become energized. The energization of the receiving relay 34 serves to light ared indicating lamp to inform the operator that the circuit breaker s3 is closed.

It will be observed that a green light 69 will be lighted when relay 34 of the second receiver fill is deenergized toindicate to the operator that the circuit breaker 53 is in the open position.

In describing the operation of the synchronizing system, it will be assumed that the circuit breaker i3 is in the open position. The supervisor y relay t4 deenergized and the generator.

$5 is not functioning. The operatingswitch 6| is. open and, since generator is not functioning, relay 34 of receiver 53 is deenergized and, as a result, actuating relay M5 is also deenergized. It will also be assumed that the filamentsof all of the vacuum tubes are connected to suitable current sources and that suitable plate and grid potentials are supplied to the proper indicated connections from a suitable power source not shown. 1

The synchronizing switch 58 is closed and the operator watches the movement of the pointer of the indicating meteril. When it has reached the predetermined. point along the scale where synchronism is indicated between the two portions of the system, the operator closes switch 6! thereby initiating the operation of generator ti! and the receiving relay 34 of the receiver 63 is in turn energized. As set forth hereinbefore, the energization of relay 34, of receiver 63, causes the energization of actuating relay 4t whichserves to complete acircuit for energizingthe closing.

coil Mto operate the circuit breaker 13 to theclosed position. i Upon the closure of the circuit breaker, supervising relay M is energized thereby causing enerator' to function and operate the receiver 6'! to indicate, by lighting red signal lamp 68, that the circuit breaker A3 is closed.

When it is desired to open the circuitbreakerj 43, the operator opens operating switch 51 thereby arresting the functioning of generator Ell and, as a result, deenergizing relay 3.4 of the receiver. 53. actuating relay 46 isimmediately deenergized and completes a circuit for energizing the trip coil 55' to elfect the opening of circuit breaker 43. The supervisory relay 64 is then deenergized and the functioning of generator 65 is arrested and, as a result, relay 34 of receiver Bl is 'deenergized causing the red signal lamp 68. to be extinguished and the green signal lamp 69 to be lighted.

:It will be readily apparent to those skilled in the art thatthe generator 59 may be operated only'for a suilicient length of time to close the circuit breaker 6 3 and that it may then be deen-ergized. In order to trip the circuit breaker 43, withthis arrangement, a second generatormaybe provided fo-r causing the energization of trip coil 45.

'Since further changes may. be made in the above circuitsanddiiferent einbodhnents of the invention may be made without departing from the scope thereof, it is. intended that all matter contained in the foregoing description or shown inthe accompanying drawing should be interpreted asillustrative and not in a limiting sense. I claim as my. invention: A l. A system for synchronizing two electrical systems having applied thereto: alternating currents of predeterminedfrequency comprising, in

combination, a first station, a second station, a single circuit connecting the stations, oircuit closing meansat the second station'for connecting the electrical systems together, transmitting vacuum tube means at the second station re sponsive to the frequencies ofthe systems for applying said frequencies to the single circuit.

connecting the stations, receiving vacuum tubemeans at the station for receiving the fre quencies from the single circuit, indicating means connected to thereceiving means to indicate the degree of synchronismbetween the systems, and control and supervision means connected to the circuit at the first station to actuate the circuit or: i

receiving means at the second station for con-- 1 rents of predetermined frequency comprising, in

combination, a first station, a second station, a single circuitconnecting the stations, circuit closing means at the second. station for connecting the electrical systems together, transmitting vacuum tube means at the second station responsive to the frequencies of the systems for applying said frequencies to the circuit connecting the stations, receiving vacuum tube means at the first station for receiving the frequencies from the single circuit connecting the stations, indicating means connected to the receiving means to indicate the degree of synchronisrm between the systems, and means at the first station for applying a control frequency to the circuit to actuate the circuit closing means at the second station.

3. A system for synchronizing two electrical systems having applied thereto alternating currents of predetermined frequency comprising, in combination, a first station, a second station, a single circuit connecting the stations, transmitting vacuum tube means at the second station responsive to the frequencies of the system for applying said frequencies to the circuit connecting the stations, receiving vacuum tube means at the first station for receiving the frequencies from the circuit, indicating means connected to the receiving means to indicate the degree of synchronism between the systems, a circuit breaker at the second station for connecting the systems together, an actuating relay for controlling the operation of the circuit breaker, a generator at the first station for applying oscillations of a predetermined frequency to the circuit, amplifying means at the second station for amplifying the oscillations applied to the circuit by the generator, receiving means connected to the amplifying means and responsive only to the frequency of said generator, a relay actuated by the receiving means on application of oscillations. thereto from the generator at the first station to control the operation of the actuating relay, a generator at the second station for applying oscillations of a predetermined frequency to the circuit, a relay energized on closure of the circuit breaker for initiating the functioning of the generator at the second station, receiving means at the first station connected to the circuit and responsive only to the frequency applied thereto by the generator at the second station, a relay actuated by the receiving means at the first station, and signalling means controlled by the last named relay for indicating at the first station the position of the circuit breaker.

4. A system for synchronizing from a first station two electrical systems at a second station having applied thereto alternating currents of predetermined frequencycomprising, in combination, a circuit breaker for connecting the said systems together, a single circuit connecting the stations, transmitting vacuum tube means at the second station responsive to the frequencies of the systems for applying them to the single circuit, receiving vacuum tube means at the first station for receiving the frequencies transmitted over the single circuit, indicating means connected to the receiving means to indicate the degree of synchronism between the systems and means including a vacuum tube transmitting means at the first station and a vacuum tube trolling over said single circuit the operation of the circuit breaker at the second station.

5. A system for synchronizing'two electrical systems having applied thereto alternating currents of predetermined frequency comprising, in combination, a first station, a second station, a. single circuit connecting the stations, circuitclosing means at the second station for connecting the electrical systems together, transmitting vacuum tube means at the second station responsive to the frequencies of the systems for applying said frequencies to the single circuit connecting the stations, receiving vacuum tube means at the first station for receiving the frequencies from the single circuit, indicating means connected to the receiving means to in-,

dicate the degree of synchronism between the systems, transmitting means at the first station operable to apply-a predetermined frequency to the single circuit, receiving means at the second station responsive to said predetermined frequency, and means controlled by the receiving means for controlling the operation of the circuit closing means.

6. A system for synchronizing two electrical systems having applied thereto. alternating currents of predetermined frequency comprising, in combination, a first station, a second station, a single circuit connecting the stations, circuit closing means at the second station for connecting the electrical systems together, electronic transmitting means at the second station responsive to the frequencies of the systems for applying said frequencies to the circuit connecting the stations, electronic receiving means at the first station for receiving the frequencies from the single circuit connecting the stations, indicating means connected to the receiving means to indicate the degree of synchronism between the systems, electronic transmitting means at the second station for applying an indicating frequency to the single circuit, electronic receiving means at the first station responsive to said indicating frequency operable to indicate the position of the circuit closing means at the second station. l

7. A system for synchronizing two electrical systems having applied thereto alternating currents of predetermined frequency comprising, in combination, a first station, a second station, a single circuit connecting the stations, transmitting vacuum tube means at the second station responsive to the frequencies of the systems for applying said frequencies to the single circuit connecting the stations, amplifying means at the first station for amplifying the frequencies applied to the single circuit, receiving vacuum tube means at the first station connected to the amplifying means thereat for receiving the said frequencies from the circuit, indicating means connected to the receiving means to indicate the degree of synchronism between the systems, a circuit breaker at the second station for connecting the systems together, an actuating relay for controlling the operation of the circuit breaker, a generator at the first station for applying oscillations of a predetermined frequency to the circuit, amplifying means at the second station for amplifying. the oscillations applied to the circuit by the generator, receiving means connected to the amplifying means and responsive only to the frequency of said generator, a relay actuated by the receiving means on application of oscillations thereto from the generator at the first station to control the operation of the actuating relay, a generator at the second station for applying oscillations of a predetermined frequency to the circuit, a relay energized on closure of the circuit breaker for initiating the functioning of the generator at the second station, additional receiving means at the first station connected to the amplifying means thereat and responsive only to the frequency applied thereto by the generator at the second station,

a relay actuated by the receiving means at the 7 first station, and signalling means controlledby the last named relay for indicating at the first 5 station the position of the circuit breaker.

RALPH N. STODDARD. 

